The Request for an Opinion by Le Minor and Popoff 1987, proposing designation of 'Salmonella enterica' (ex Kauffman and Edwards 1952) Le Minor and Popoff 1987 as the type and only species of the genus Salmonella Lignieres 1900 (Approved Lists 1980), has not been positively decided upon by the Judicial Commission. However, many bacteriologists use the name 'Salmonella enterica'. To avoid further confusion, it is requested to reject the name Salmonella choleraesuis (Smith 1894) Weldin 1927 (Approved Lists 1980), to recognize the species Salmonella enterica, to conserve the name Salmonella typhi (Schroeter 1886) Warren and Scott 1930 (Approved Lists 1980), and to emend the genus Salmonella with the establishment of a neotype species, Salmonella enterica.

The proposals of Le Minor and Popoff in 1987 and again of Euz?by in 1999 on the type species of the genus Salmonella are in violation of Rule 20a of the Bacteriological Code (1990 Revision) and should be rejected. The introduction of the term 'neotype species' should be rejected. The specific epithet choleraesuis in the binary combination Salmonella choleraesuis should be conserved. The serovar name Choleraesuis should be changed to Hogcholera.

The nomenclature of the genus Salmonella has reached an unsatisfactory state of affairs, with two systems of nomenclature in circulation. One system, proposed in the 1980s by Le Minor and Popoff, has received wide acceptance, although it does not conform to the rules of the Bacteriological Code. The other system, which conforms to the rules of the Bacteriological Code, is being used by an ever-decreasing minority. As a result of a number of recent Requests for an Opinion, the Judicial Commission of the International Committee on the Systematics of Prokaryotes has issued an Opinion (Opinion 80) with the intention that it should solve these discrepancies. However, like all Opinions, it is limited to matters of nomenclature and does not help to interpret the taxonomic consequences. The Judicial Commission has therefore asked experts in the field of nomenclature and taxonomy to write a commentary on the nomenclatural and taxonomic consequences of Opinion 80. The present article explains the nomenclatural consequences of Opinion 80, together with a clear presentation of the taxonomy that results when applying the currently widely accepted interpretation that the genus Salmonella currently includes only two species.

The Judicial Commission of the International Committee for Systematics of Prokaryotes has decided that the type species of the genus Salmonella Lignieres 1900 is Salmonella enterica (ex Kauffmann and Edwards 1952) Le Minor and Popoff 1987 and that the type strain of this species is strain LT2T. In addition, the epithet enterica in Salmonella enterica is conserved over all earlier epithets that may be applied to this species.